1. Field of the Invention
This invention relates to sports training apparatus and more particularly to a portable ball projecting apparatus for serving and setting balls for practice of the game of volleyball.
2. Description of the Prior Art
Ball serving and throwing machines are well known and are widely used in the practice of many sports such as baseball, softball and tennis. Such machines conventionally employ a motor which, acting through a speed reduction and/or force multiplying mechanism, retracts a throwing or striking arm against the force of a resilient biasing means, then releases the arm to propel the ball, either by impact or centrifugal force, along the desired trajectory. Pneumatic ball throwing devices are also known and are employed enabling players to effectively practice various aspects of games such as tennis, baseball, softball and volleyball.
It is also known to provide manually actuated ball throwing and/or serving mechanisms to enable a person unskilled in a particular game to effectively assist a player in practicing his game. One such machine is shown, for example, in U.S. Pat. No. 3,804,071 which discloses a volleyball practicing machine employing a pivoted, spring-biased, manually retracted ball striking arm. A plurality of pivots are provided on the machine for supporting the striking arm at different distances from the resilient biasing means to permit limited selective variation of the force delivered to the balls by the striking arm.
The known prior art volleyball projecting machines have not been entirely satisfactory for various reasons. For example, the known pneumatic volleyball serving machines generally have not been capable of adjustment to substantially vary the velocity and trajectory of the ball to enable the efficient use of the machine both to practice the return of a service and of spiking the ball, both of which are important aspects in the game of volleyball. The manually operable volleyball practice machines have also been unsatisfactory in that they require substantial physical labor and have been relatively slow in operation so that maximum utilization of the players practice time is not achieved.
It is, accordingly, a primary object of the present invention to provide an improved ball projecting apparatus capable of operation to project volleyballs along various trajectories and at various velocities to enable volleyball players to practice a variety of aspects of the game.
Another object of the present invention is to provide such a ball projecting apparatus which is relatively light in weight and easily movable by a single individual to facilitate storage and setting up of the apparatus.
Another object of the invention is to provide such a ball projecting apparatus having improved means for varying the trajectory and velocity of a ball projected from the apparatus.